中国8个不同来源DDGS蛋公鸡氨基酸代谢率及评价方法相关性研究

 【目的】寻求快速评价DDGS氨基酸代谢率的方法,为家禽生产中合理利用DDGS资源提供科学依据。【方法】选择45只、（2.6±0.2）kg的健康成年海兰褐蛋种公鸡,采用2×9不完全拉丁方设计,随机分为9个处理组,每组5个重复,每个重复1只鸡,进行2期代谢试验。用无氮饲粮法测定了中国8个不同来源DDGS（A—H）的氨基酸代谢率,并研究其与DDGS的色泽和水溶物含量的相关性。【结果】8个DDGS的总氨基酸表观代谢率和真代谢率范围分别为60.18%—74.06%和74.13%—89.15%,赖氨酸表观代谢率低于60%,真代谢率为63.08%—82.07%。DDGS的水溶物含量与赖氨酸真代谢率存在高度正相关（R²=0.7601）。【结论】不同来源DDGS间的各种氨基酸代谢率有不同程度的差异,通过测定DDGS的水溶物含量可以初步估测鸡赖氨酸真代谢率。     

精料干酒糟及其可溶物水平对奶牛产奶性能及氮排泄的影响

本试验旨在研究精料中不同干酒糟及其可溶物(DDGS)水平对奶牛产奶性能及氮排泄的影响。选择30头体重、胎次、产奶量、乳成分和泌乳天数[(115±14)d]相近的健康中国荷斯坦牛,随机分为5个组,对照组精料不添加DDGS,试验Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组分别以10.0%、17.5%、25.0%和32.5%的DDGS等比例替代精料中花生粕、棉籽粕、豆粕和玉米。预试期15 d,正试期60 d。结果表明:1)干物质采食量,试验Ⅰ组、Ⅱ组、Ⅲ组及对照组显著高于试验Ⅳ组(P<0.05),而这4个组间无显著差异(P>0.05);粗蛋白质采食量,4个试验组间无显著差异(P>0.05),试验Ⅰ组、Ⅱ组与对照组之间无显著差异(P>0.05),而试验Ⅲ组和Ⅳ组显著低于对照组(P<0.05)。2)日均产奶量,对照组和试验Ⅰ组、Ⅱ组、Ⅲ组整个正试期的平均值均显著高于试验Ⅳ组(P<0.05),分别比试验Ⅳ组高6.17%、8.27%、9.06%和9.59%,对照组和试验Ⅰ组、Ⅱ组、Ⅲ组间则无显著差异(P>0.05)。3)对照组和4个试验组间各乳成分含量均无显著差异(P>0.05)。4)4个试验组总氮排泄量整个正试期的平均值分别比对照组下降4.19%、9.36%、12.08%和18.02%,各组间均存在显著或极显著的差异(P<0.05或P<0.01)。综合考虑奶牛产奶性能和氮排泄,在本试验条件下,奶牛精料中适宜的DDGS水平为25.0%。     

Physicochemical assessment and bioactive properties of condensed distillers solubles,a by-product from the sorghum bio-fuel industry

Large volumes of condensed distillers solubles (CDS) are generated as by-products, from the sorghum bioethanol industry. The objective was to assess the physico-chemical and bioactive properties of CDS. The unfractionated CDS showed the highest content of phenolic compounds (16 mg GAE/g), antioxidant (522 μM Trolox/g) and antimicrobial activity (MIC 1%(w/v) against Campylobacter spp.) compared to its extracts. The water and methanol extracts also showed high levels of phenolic compounds and antioxidant activity (11.6 and 9.2 mg GAE/g and 349 and 409 μM Trolox/g respectively), followed by ethanol and acetone extractions (7.5 and 6.6 mg GAE/g; 337 and 346 μM Trolox/g respectively). A positive correlation was revealed between total phenol and antioxidant activity. The main phenolic compounds found in the extracts were protocatechuic acid, 4-hydroxybenzoic acid, taxifolin, ferulic acid, cinnamic acid and p-coumaric acid. This study indicates the potential of using CDS as a functional ingredient for other food and feed applications.     

Anthelmintic activity of Cocos nucifera L. against sheep gastrointestinal nematodes

The development of anthelmintic resistance has made the search for alternatives to control gastrointestinal nematodes of small ruminants imperative. Among these alternatives are several medicinal plants traditionally used as anthelmintics. This work evaluated the efficacy of Cocos nucifera fruit on sheep gastrointestinal parasites. The ethyl acetate extract obtained from the liquid of green coconut husk fiber (LGCHF) was submitted to in vitro and in vivo tests. The in vitro assay was based on egg hatching (EHT) and larval development tests (LDT) with Haemonchus contortus. The concentrations tested in the EHT were 0.31, 0.62, 1.25, 2.5 and 5 mg ml⁻¹, while in the LDT they were 5, 10, 20, 40 and 80 mg ml⁻¹. The in vivo assay was a controlled test. In this experiment, 18 sheep infected with gastrointestinal nematodes were divided into three groups (n = 6), with the following doses administered: G1—400 mg kg⁻¹ LGCHF ethyl acetate extract, G2—0.2 mg kg⁻¹ moxidectin (Cydectin^®) and G3—3% DMSO. The worm burden was analyzed. The results of the in vitro and in vivo tests were submitted to ANOVA and analyzed by the Tukey and Kruskal–Wallis tests, respectively. The extract efficacy in the EHT and LDT, at the highest concentrations tested, was 100% on egg hatching and 99.77% on larval development. The parameters evaluated in the controlled test were not statistically different, showing that despite the significant results of the in vitro tests, the LGCHF ethyl acetate extract showed no activity against sheep gastrointestinal nematodes.     

李子丰产栽培技术研究

李子具有易栽植,生长势强,开花结实早的特点,试验结果表明花红李、奈李和金沙李3品种中种植花红李和奈李可获较高收入,合理密植可提高李子单位面积产量和产值,赤霉素能促进李子开花结实。在滇东南岩溶地区宜发展种植奈李和花红李2品种,采用2m×3m株行距定植,林下混种矮秆农作物,于初花和幼果期各喷1次200mg/kg浓度赤霉素可取得良好的经济效益。     

Germplasm Sources for Improvement of Forage Quality in Lotus corniculatus L. and L. uliginosus Schkuhr (Fabaceae)

Extensive germplasm resources are present in collections of Lotus corniculatus and L. uliginosus, two forage species that are valuable in situations where other legumes are not persistent. Naturalised populations in many regions are the primary gene pool for genetic improvement of these species and interspecific hybrids are an important source of variation for agronomic and forage quality traits. Although previous research has provided evidence that selection for optimal levels of condensed tannins and herbage productivity are feasible breeding objectives, less is known about correlations of condensed tannin with other parameters of nutritive value. A germplasm collection of 38 accessions in both species from 9 geographic regions was used as a data base to determine these correlations. Forage of each accession was sampled in two successive years from a field site in south-eastern Australia and analysed for condensed tannin, in vitro digestible dry matter, nitrogen, acid detergent fibre and neutral detergent fibre. In both species condensed tannin was negatively correlated with in vitro digestible dry matter and nitrogen. This result helped to identify potentially valuable accessions with low condensed tannin (<4% of dry weight) and high in vitro digestible dry matter (>70%). One of these was an interspecific hybrid of L. uliginosus and L. corniculatus, confirming the view that interspecific hybridization would be a valuable avenue for improvement of agronomic and forage quality characters in Lotus species.